An injection tube for construction joints on concrete buildings is known from DE-U 8,425,518, having an essentially cylindrical wall which is permeable to liquid and is made of flexible material, such as rubber or plastic, in which the wall has a slot, extending over its length, for the outlet of the injection liquid, the wall in the region of the slot has a depression, extending axially likewise over the length of the wall, for receiving a strip which covers the slot and is made of a material which is compressible under the pressure of the injection liquid, and in which the wall with the strip is enclosed by a tube of material which is permeable to liquid. Such an injection tube has disadvantages in terms of manufacture and, owing to the relatively narrow outlet slot compared to the width of the depression, relatively high compression forces are required without being able to achieve a reliably uniform distribution of the injection liquid over the circumference of the injection tube.
These disadvantages are avoided to a great extent in the injection tube known from DE-A 3,512,470, in that a plurality of radial openings in the basic body and the assigned depressions and strips are distributed over the circumference of the basic body with angular symmetry in relation to the longitudinal mid-axis. However, this requires greater production expenditure.